Island



P. GRINNELL.

AUTOMATIC TIRE BXTINGUISHING APPARATUS.

(No Model.)

Patented Oct. 25, 1887.

IIIH

IIIIIHIHI lllllllill N. PETERS. mammogram", wur-iugm. DTC.

UNITED STATI-3s PATENT OFFICE.

FREDERICK GRINNELL, OF PROVIDENCE, RHODE ISLAND.

AUTOMATIC FIRE-EXTINGUISHING APPARATUS.

SPECIFICATION forming part of Letters Patent No. 372,219, dated October 25, 1887.

I Application filed December 30, 1886. Serial No. 222,984. (No model.)

' of Rhode Island, have invented a new and lOV useful Improvement in Automatic Fire-Exiinguishing Apparatus, of which the following is a specification. A

My invention relates to an improvement upon a dry-pipe77 system of lire-extinguish ing apparatus-such as shown in Patent No. 249,171, granted to me November 8,1881; and the invention consists of certain combinations of devices whereby the air-pressure in the distributing-pipes A extending throughout the building to be protected is brought in direct opposition to the water-pressure in the supply-pipe, so as to keep the water from flowing int-o the distributing-pipes, except when the air-pressure therein is relieved by the opening of one or more of the automatic sprinklers attached thereto.

In another application of even date herewith, Serial No. 222,985, I have shown a device upon which I have made claims covering such a combination broadly. In this case I show a modified form for accomplishing the same result by somewhat different means.

In the accompanying drawings, Figure 1 shows a sectional view of my improved apparatus in its closed or normal position. Fig. 2 is a similar view showing the device in its open or operative position.

The distributing-pipes 1 are provided with automatic fire extinguishers or sprinklers 2, which may be held closed by apiece or ajoint of fusible metal that will melt and allow the iluid within the pipe to escape upon the oocurrence of atire in their vicinity. The watersupply pipe 3 connects with the source of waterpressure and communicates, through a port closed by valve 8, with the chamber or casing 5, and from this chamber another port closed by valve 9 leads to the distributing-pipe. This valve 9 isa plain check-valve, and serves to retain the air-pressure that is normally maintained in the distributing pipe. The valve 8 is also a check-valve, and serves to keep the water from owing from the supplypipe. It has an extended stem, 7, supporting a diaphragm, 10, which separates the chamber 5 from another chamber, 11, that communi- Cates through pipe 12 with the distributingpipe. The diaphragm is made larger in area than the water-valve 8, so as to more than' compensate for the greater pressure of the water over that of the air, so that the watervalve is held closed by the direct action of the air-pressure in the distributing-pipes. sist the diaphragm in performing its function of holding the water-valve closed, the intermediate chamber, 5, is kept under a pressure less'than that in the'distributing-pipes, andthis is done, notwithstanding any leakage that may occur at the valves 8 or 9, by means of a drip-pipe, 13, which communicates normally with the atmosphere. This drip-pipe is provided with a check-valve, 14, which allows the water to slowly leak past but closes up against a seat when the water` is fully turned on by the opening of valve 8. No claim is made in this case on this feature however. A cock, 15, in a by-pass, 16, around the valve 8, allows the water to be turned on at will into the intermediate chamber and distributing-pipes. A cock, 17, in pipe 12 allows the water to be drawn off from the distributing-pipes. Air may be pumped into the distributing-pipes by attaching an air-pump to pipe 27, and a pressuregage, 18, serves to indicate at all times the pressure in the system. A cock, 19, in the pipe 12 is used to disconnect the chamber 11 from the distributing-pipe 1, so as to facilitate operations upon the valves. A plate-spring, 22, is arranged so as to pass under valve-stem 7,When the valve is moved from its seat, so as to hold it open. To replace the valve the hand-hole plug 21 is taken out and the spring pushed to one side. This stop is not claimed herein, it forming an element in the claims of the other case above referred to. rIhe distributing-pipes being charged with air under a light pressure, and the valves and diaphragm being in their' closed positions, as shown in Fig. 1, the cock 19 being open and the cocks 15, 17, and 27 being closed, the apparatus will have the water standing in it, as shown, and will be ready for action. Should nowa tire occur anywhere in the building, the nearest sprinkler will open, and the pressure inthe distributing-pipes being thus released the valve 8, `not being held any longer bya pressure back of the diaphragm 10, will be forced To as- IOO from its seat by the water and held open by stop 22, while the water flowing into chamber 5 will shut the check-valve 14, and opening the valve 9 will fill the distributingpipe, and escaping` by the open sprinkler will extinguish the lire.

In the other case above referred to I have made claims covering the feature of a watervalve held closed by the direct action of the air-pressure, and I therefore limit this case to the particular invention described. I do not wish,l1owever, to limit myself to the use ofthe particular form of diaphragm shown for holding the watervvalve closed, as it is evident that any means closing the opening between chambers 5 and 11 and movable therein may be used to hold the val ve. Thus I would consider that a piston sliding ina cylinder would be the equivalent ofthe diaphragm, and I therefore wish it to be understood that I use the term diaphragm as covering such equivalent means.

The chamber ll is to be considered as if it were one with the distributingpipe, the cock I9 performing no function whatever in the ordinary operation of the device.

By the expression light air-pressure7 I mean air or gas underapressurelight as compared with the pressure of the water in the supply-pipe.

Having thus described my invention, what I claim as new is- The combination of the water-supply pipe charged with water under pressure, the dis-Y tributing pipes and sprinklers charged with light air-pressu re, an intermediate chamber or casing communicating normally with the atmosphere, a check-valve preventing the escape of fluid from the distributing-pipes to the intermediate chamber, a \vatervalve preventing the flow of water from the supply-pipe to said chamber, and a movable diaphragm, substantially as described, connected directly to the water-valve and closing an opening between the intermediate chamber and a chamber communicating with the distributing-pipes, so as to oppose and balance the water-pressure by the light air-pressure in the distributingpipe.

FREDERICK GRINNELIJ. Titnessesz W. H. TnURsroN, W. H. KNIGHT. 

